Can't get "Grounding" Shadows w/Rad Setup

[MegaPixel]

I've been pulling my hair out for a while now trying to get a single Daylight System to illuminate my Interiors indirectly, yet still provide enough shadow casting power to "ground" my interior objects to the floor or walls. I've been living with the "floating" object syndrome for a while now and it's time to coem down.

 

I attached a very simple scene file along with this post that was used to produce the rendering also attached. It is my hope that some of you more ambitious problem solvers might nab it and see what you can reproduce. The file is MAX 7 based and should also work in VIZ 2006.

 

My area of focus is on the array of tall, thin boxes in the middle of the room. I am looking for darker, more noticiable shadow casting of these objects to help better convince me that they belong in the shot.

 

If I have to add additional lights to do this then so be it. I guess I just need to hear what some others have to say about it first. Thanks in advance for some help. MegaPixel

[oluv]

your shadows are there, but you filter them away!

i loaded your scene, let it process until 90% and changed exposure a bit. didn't do anything to the materials, still i don't know why my colors are so different from yours.

 

i regathered the scene with the same settings as yours, but with turned off filtering and turned down filter radius to 0,5 pixel. now we have all the desired shadows and a nice "maxwell-effect". to avoid all the noise you have to use either more samples and increase rendering-time or experiment with adaptive sampling, which still is better than filtering all details away already from the beginning.

in the second image i used 2 pixels filter radius and doubled the samples to 200, no adaptive sampling. you see the shadows are still there, the noise is gone, although not entirely but the rendering time has doubled too

[MegaPixel]

oluv,

 

Which filter setting is actually blurring the shadows away? Is it the Indirect and Direct Light filtering in the Rad parameters area or is it the Regather filter radius only? If it is the Regather radius, then that value should never go above 2/2.5 or does that still depend on the target resolution?

 

I also did "Not" shoot the skylight in my radiosity solution. Would that have made any difference for regather? What do I have to do to get these shadows to show up when reusing direct illumination instead of regathering?

 

Thank you so much for being the first to step up and set me straight. I am very gratful for your help on the matter. - David

[oluv]

oluv,

 

Which filter setting is actually blurring the shadows away? Is it the Indirect and Direct Light filtering in the Rad parameters area or is it the Regather filter radius only? If it is the Regather radius, then that value should never go above 2/2.5 or does that still depend on the target resolution?

 

it is the regather radius that makes the difference. i attached you 3 images, all rendered with 100samples, but the first with 2 pixel filtering radius, 4 pixel and 8 pixel.

of course it is dependend on the resolution, so if you render twice the sice, you can also double the filtering, maybe even more with bigger sizes, depends on the details to be seen.

 

I also did "Not" shoot the skylight in my radiosity solution. Would that have made any difference for regather? What do I have to do to get these shadows to show up when reusing direct illumination instead of regathering?

i doubt you would manage to get them show up only with the rough radiosity solution. you would need a very fine mesh and processing up to 100% to get rid of all mesh artefacts. you could try with adaptive meshing, but as i heard it has also its flaws.

 

radiosity is not easy to manage, but has one big advantage, the possibility of moving around in the model in real-time and adjusting exposure, contrast etc and directly seeing the results. regather takes some time, it is not the fastest, although vray with highest quality can also take quite a time. i tried it yesterday on your scene and didn't manage better in shorter time.

[MegaPixel]

I made another test pass based on the tips you gave me oluv.

 

At 800x600 (27 minutes on a P4 3.4 Ghz Machine)

 

Global Mesh at 4" solved to 95%

No Ind. or Dir. Filtering

Regathered @ 350 Samples with 1 Pixel Radius

 

1 Daylight System used (Skylight set to Partially Cloudy Day)

 

The shadowing is faint, but it appears as if it's all in the regather pixel radius value. I'm having a hell of a time getting rid of regather noise with that small of a value however...

 

David

[MegaPixel]

OK, now I have generated some new issues (See attached image)

 

As you can see from the Image posted previously, I had managed to get all of these objects to actually cast indirect shadows under 1 Daylight System.

 

I have created a new interior and merged the Daylight System and Objects from the scene above into it (assuming everything would work right). As you can see in the newly attached image, the Stools don't want to cast anything but the Blocks are still casting?? Does anyone have any ideas about what might cause this?

 

The Walls, Trims and Floor are Advanced Light Overide materials with their reflectance & color bleed values down to about .5 Am I using these materials improperly? When should I use the Adv Light Overide materials - if at all?

 

Thanks a ton for the info received so far. - David

[oluv]

have you reset the radiosity solution after importing the new objects? have you seen inside their properties if they recieve/cast eveything etc?

is your mesh still 4"? and how far have you processed the solution? maybe the mesh is not fine enough? you will get much less details with a rougher mesh. try to set the size to 20" or 30", process the radiosity solution and regather, you will see that the fine details will all disappear compared to the fine mesh.

other than that i have no idea what could be wrong!

[MegaPixel]

Yes I've looked at all of the things you've mentioned. I guess I could try adaptivly subdividing the floors,walls and trim down to 1"? I'll let you know by the end of the day if things get worse or better.

 

David